SYDNEY, Australia (AP) -- A tiny frog species thought by many experts to be extinct has been rediscovered alive and well in a remote area of Australia's tropical north, researchers said Thursday.

The 1.5 inch-long Armoured Mistfrog had not been seen since 1991, and many experts assumed it had been wiped out by a devastating fungus that struck northern Queensland state.

But two months ago, a doctoral student at James Cook University in Townsville conducting research on another frog species in Queensland stumbled across what appeared to be several Armoured Mistfrogs in a creek, said professor Ross Alford, head of a research team on threatened frogs at the university.

Conrad Hoskin, a researcher at The Australian National University in Canberra who has been studying the evolutionary biology of north Queensland frogs for the past 10 years, conducted DNA tests on tissue samples from the frogs and determined they were the elusive Armoured Mistfrog.